Add Thread Certification 5.2.6 to automated test. (#784)

tests/scripts/Makefile.am

@@ -49,6 +49,7 @@ EXTRA_DIST                                                         = \
     thread-cert/Cert_5_2_03_LeaderReject2Hops.py                     \
     thread-cert/Cert_5_2_04_REEDUpgrade.py                           \
     thread-cert/Cert_5_2_05_AddressQuery.py                          \
+    thread-cert/Cert_5_2_06_RouterDowngrade.py                       \
     thread-cert/Cert_5_2_07_REEDSynchronization.py                   \
     thread-cert/Cert_5_3_01_LinkLocal.py                             \
     thread-cert/Cert_5_3_02_RealmLocal.py                            \
@@ -153,6 +154,7 @@ check_SCRIPTS                                                     += \
     thread-cert/Cert_5_2_03_LeaderReject2Hops.py                     \
     thread-cert/Cert_5_2_04_REEDUpgrade.py                           \
     thread-cert/Cert_5_2_05_AddressQuery.py                          \
+    thread-cert/Cert_5_2_06_RouterDowngrade.py                       \
     thread-cert/Cert_5_2_07_REEDSynchronization.py                   \
     thread-cert/Cert_5_3_01_LinkLocal.py                             \
     thread-cert/Cert_5_3_02_RealmLocal.py                            \

tests/scripts/thread-cert/Cert_5_2_06_RouterDowngrade.py

@@ -0,0 +1,73 @@
+#!/usr/bin/python
+#
+#  Copyright (c) 2016, The OpenThread Authors.
+#  All rights reserved.
+#
+#  Redistribution and use in source and binary forms, with or without
+#  modification, are permitted provided that the following conditions are met:
+#  1. Redistributions of source code must retain the above copyright
+#     notice, this list of conditions and the following disclaimer.
+#  2. Redistributions in binary form must reproduce the above copyright
+#     notice, this list of conditions and the following disclaimer in the
+#     documentation and/or other materials provided with the distribution.
+#  3. Neither the name of the copyright holder nor the
+#     names of its contributors may be used to endorse or promote products
+#     derived from this software without specific prior written permission.
+#
+#  THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
+#  AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+#  IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+#  ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE
+#  LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
+#  CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
+#  SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
+#  INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
+#  CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
+#  ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
+#  POSSIBILITY OF SUCH DAMAGE.
+#
+
+import time
+import unittest
+
+import node
+
+LEADER = 1
+ROUTER1 = 2
+
+class Cert_5_2_06_RouterDowngrade(unittest.TestCase):
+    def setUp(self):
+        self.nodes = {}
+        for i in range(1, 26):
+            self.nodes[i] = node.Node(i)
+            self.nodes[i].set_panid(0xface)
+            self.nodes[i].set_mode('rsdn')
+            self.nodes[i].set_router_selection_jitter(1)
+            if i != ROUTER1:
+                self.nodes[i].set_router_upgrade_threshold(32)
+                self.nodes[i].set_router_downgrade_threshold(32)
+
+    def tearDown(self):
+        for node in list(self.nodes.values()):
+            node.stop()
+        del self.nodes
+
+    def test(self):
+        self.nodes[LEADER].start()
+        self.nodes[LEADER].set_state('leader')
+        self.assertEqual(self.nodes[LEADER].get_state(), 'leader')
+
+        for i in range(2, 25):
+            self.nodes[i].start()
+            time.sleep(5)
+            self.assertEqual(self.nodes[i].get_state(), 'router')
+
+        self.nodes[25].start()
+        time.sleep(5)
+        self.assertEqual(self.nodes[25].get_state(), 'router')
+
+        time.sleep(10)
+        self.assertEqual(self.nodes[ROUTER1].get_state(), 'child')
+
+if __name__ == '__main__':
+    unittest.main()